1. Field of the Invention
The present invention relates to an applicator and tissue fastening method to perform a procedure for fastening tissues through a natural orifice.
2. Description of Related Art
Laparoscopic surgery which is transcutaneous insertion of medical instruments as a treatment of body organs is well known. This method is less invasive compared to incising the abdomen, and quick recovery is anticipated.
A medical instrument used for laparoscopic surgery has a shaft made of hard material inserted in the body transcutaneously, with forceps and so on provided at the front end of the shaft. For example, a treatment instrument used in applications such as connecting hollow organs is disclosed in Japanese Unexamined Patent Application, First Publication No. 2005-193044. This intraluminal anastomosis device has a grasper that can freely open and close fitted to the front end of the shaft, and a fastening tool inserted in the shaft.
The fastening tool can be pushed out from the front end of the shaft by the protruding device located proximally with respect to the operator. The fastening tool is formed by annealing (or heat treating) shape memory alloy into a flat coil shape and inserting it in the shaft in the elongated condition. When the fastening tool is used, the clamp is pushed out from the protruding device and inserted into the body. The fastening tool is heated by body temperature and restored to its original coil shape. The hollow organs are joined by the restored fastening tool.
Other examples of dispensing the fastening tool are disclosed in the international publication number WO2002/019923. Here, the fastening tool is pushed out from the needle and dispensed to the tissue. For this reason, a anchor is provided to control the depth to which the needle pierces the tissue and the amount of the fastening tool dispensed into the tissue. When performing the procedure, the instrument containing the fastening tool and the needle is punctured to the tissue. The needle is advanced to pierce the layers of tissue, and the position of the fastening tool is fixed by the anchor. Thereafter, the needle is pulled out from the tissue. The fastening tool does not move because of the anchor; therefore, its front end part remains inside of the inside layer of tissue. When the instrument is removed from the tissue, the rest of the fastening tool remains outside of the outside layer of tissue. When the fastening tool is restored into its original coil shape, the layers of the tissue are fastened.